The primary objective of this project is to develop new software tools that utilize laser graphics to help the clinical investigator perceive significant information in study datasets. The first step, in Phase I, is to identify graphical data visualization techniques suitable for clinical data, to develop prototype implementations of these techniques, and to evaluate their utility in relation to cancer and AIDS data through a collaboration with investigators at the Harvard School of Public Health. The major technical innovation in this project is expected to be the development of novel exploratory data analysis techniques oriented towards laser printer presentations of large volumes of clinical study data. The major health-related contribution is hoped to be the generation of new clinical insights through the increased ability of the investigator, assisted by the new tools, to notice important patterns in patient data. The software design from Phase I will become the basis of a Phase II proposal to develop a full prototype for direct use and evaluation by investigators at several sites. The proposed software has substantial commercial appeal in support of clinical studies and clinical trials worldwide, and has potential application to other research involving the exploratory analysis of large datasets.